README: add missing MergeMode project config option

workflow-pr/README.md

@@ -54,6 +54,7 @@ This is the ProjectGit config file. For runtime config file, see bottom.
 | *GitProjectName* | Repository and branch where the ProjectGit lives. | no | string | **Format**: `org/project_repo#branch` | By default assumes `_ObsPrj` with default branch in the *Organization* |
 | *ManualMergeOnly* | Merges are permitted only upon receiving a "merge ok" comment from designated maintainers in the PkgGit PR. | no | bool | true, false | false |
 | *ManualMergeProject* | Merges are permitted only upon receiving a "merge ok" comment in the ProjectGit PR from project maintainers. | no | bool | true, false | false |
+| *MergeMode* | Type of package merge accepted. See below for details. | no | string | ff-only, replace, devel | ff-only |
 | *ReviewRequired* | If submitter is a maintainer, require review from another maintainer if available. | no | bool | true, false | false |
 | *NoProjectGitPR* | Do not create PrjGit PR, but still perform other tasks. | no | bool | true, false | false |
 | *Reviewers* | PrjGit reviewers. Additional review requests are triggered for associated PkgGit PRs. PrjGit PR is merged only when all reviews are complete. | no | array of strings | | `[]` |